In compressors having opposed cylinders, and especially those having multiple opposed cylinder pairs, the conventional approach is to employ the scotch yoke type or similar drive for the pistons as shown in U.S. Pat. Nos. 3,807,907; 3,826,036; 3,401,873; 4,352,640; 4,492,127; 4,316,705; 4,273,519; 4,090,430; 2,815,901; 4,373,876; 4,399,669 and 4,988,269. It can readily be seen from these patents that such drive mechanisms require considerably more complex structure, often, e.g., split compressor housings of considerable complexity, and of course more complex machining operations, than is required by the more conventional type of crankshaft, connecting rod combinations which are employed not only in compressors but also in an enormous variety of internal combustion engines and fluid handling power units, and the like. In this regard, the machining equipment and techniques for such conventional combinations represent, by far, the most efficient and inexpensive mode of construction, as well as producing compressors of maximum efficiency and longevity.
Heretofore, however, in the gas compressor field, the use of opposed cylinders and cylinder banks in concert with the aforesaid crankshaft, connecting rod combination has not been developed to a satisfactory commercial level, due at least in part to manipulatory difficulties encountered in the assembly and disassembly of the pistons within the cylinders and in the affixing of the connecting rods to the crankshaft. Such difficulties, e.g., have necessitated the consideration in research and development of split or otherwise complicated crankcase constructions.
Objects therefore of the present invention are: to provide a novel design for opposed cylinder compressors whereby the use of a crankshaft, connecting rod combination can be employed without the need for complex construction, machining or assembly operations; to provide such design which readily accommodates various types and configurations of head and valving constructions; to provide such design with crankcase structure which affords easy accessibility to the crankshaft, the connecting rod bearings and the cylinders; and to provide such design of a compressor block which is easy to cast and machine and which provides, for its weight, maximum strength and vibration counteraction.